Lubricant gun



May l2, 1959 v. GIKLEIN ETAL LUBRICANT GUN Filed Feb. 4, 1957 nitedStates Patent LUBRICANT GUNy Victor G. Klein, Defiance, and John R;Graef vandUmer C. Lyles, St. Louis, Mo., assignors to The McNeil-Machine8:' Engineering Company, Akron, Ohio, a corporation ofOhio ApplicationFebruary 4,1957, Serial No. 637,902.;

7 "Claims. (Cl. Z22-256)'.

This invention relates to lubricant guns; and vmore par.- ticularly to agrease gun of the typehaving a barrel for containing a supply of grease,a pump at one end `of the barrel, and a follower slidable in thebarrelfor ,forcing grease toward thepump.

' Among the several objects of the invention rnayV be noted; theprovision of a special follower for a grease gun ofthe class describedwhich is adapted for easy entry into agrease cartridge such as may beinserted in .the barrel of the gun, and for sliding sealing engagementin the car: tridge; the provision of a follower which adapts thegun forluse either as a cartridge-type grease .gun (in which casey agreasecartridge is inserted in the barrel) or as a bulk grease. gun (inwhich 'case there is no cartridge in` the barrel and the barrel isloaded by meansofa li'ller pump vor by suction), the follower beingadapted to'ma'k'e a tight seal to prevent by-passing of grease ineither'mode of use of the gun; and the provision of a follower havingthe stated features which is economical to manufacture and reliablein^use.v Other objects and features will bey in part apparent `and inpart pointed out hereinafter.

, The'invention accordingly comprises the constructions hereinafterdescribed, the scope of the invention beingl indicated in the followingclaims.

In the accompanying drawings, in which one of various possibleembodiments of the invention is illustrated,

Fig. 1 is alongitudinal section of a grease gun of thisV invention,illustrating a cartridge in the barrel of the-gun, and illustrating thefollower of the gun in an intermediate position in the cartridge;

` Fig. 2 is an enlarged section taken on line 2-2 of Fig. 1,'illustrating the follower near the pump of the gun;

Fig; 3 is a view similar to Fig. 2, without a cartridge inthe barrel,and showing in solid lines a packing member' ofthe follower in positionfor use of the gunas a' bulk grease gun;

Fig. 4 is a section of the packing member per se as it appears whendisassembled from the gun and uncompressed; and,

Fig. Sis a section taken on line 5-5 of Fig. l.

Corresponding reference characters indicate corre-l sponding partsthroughout the several views of the drawings.

' Referring to the drawings, agrease gun of lthis inveny tion is shownto comprise a container or barrel 1 for ntaininga supply of grease. Thebarrel may consist, for'example, of a metal tube. At one end of thebarrel 1 (this-'tend constituting the forward end ofthe barrel.) isafpump generally designatedP. The pump comprises a head 3 screwed on theforward end of the barrel and havingl albore 5 extending transverselywith respect :to the barrel. This bore constitutes the pump cylinder. Apumpplunger 7 reciprocatesin the bore or cylinder 5*.V The plungerextends out of one end ofthe cylinderk 5. (thev rearward end of thecylinder). A hand lever 9 is pin-connected at 11 adjacent one end to theend of the. plunger which extends out of the cylinder. A link 13 ispin-connected at 15 to thisend ofthe lever and pinice connectedxat 17 tothehead 3. They arrangement is such that by.swinging thelever away fromthe barrel 1, the plunger.7 is, pulled out through a priming or returnstroke, .and by swinging thev lever toward the barrel, the plunger ispushed in through a pressure stroke.

The head 3 is formed with a lateral inlet port 19 for the cylinder 5.through which grease may how from the barrel linto the cylinder 5 whenthe plunger 7 is fully retracted'through a full return stroke. In thebarrel is a follower 21.biased toward the head 3 by a spring 23 forforcing greasefrom the Vbarrel into the cylinder. The forwardy end ofthecylindery 5 is. closed by a plug 25. The head is'fo'rmed .with a lateraloutlet port 27 adjacent the frwardend ofthe cylinder.l Screwed in theoutlet port '27 is an outlet pipe 29. On the outer end of the pipe is aconventional hydraulic coupler 31. The forward end portionof thecylinder 5 is enlarged as indicated at 33 to provide a forwardly facingvalve seat 3S inward of the outlet port 27. A valve ball.37 is biasedtoward this seat by a spring 39 reacting from the plug 25. The head 3Tis provided'with a conventional filler nipple 41 (see Fig. 2)' forfilling of the'barrel 1 with bulk grease by means of a conventionaliiller pump. j

In ,accordance with this invention, the follower 21ais of specialconstruction, comprising a pair of sheet metal plates or washers 43 and45 and a resilient packing member 47,1which may be made of a suitableilexible greaseresistant synthetic rubber, or the like. The ,packingmem: ber 47 (shownper se in Fig. 4) is of special cup-shapedform,.having a base portion which comprises a at circular centralportion 49 in which there is a central opening 51 and an annular conicalflange 53 at the periphery ofl the central portion, thisflange iiaringout from the central portion, and'having. an annular wall portion 55extending back from the periphery of the flange 53. ln its unstressedortunconiined condition, this annular Wall portion" 55. is of conicalform, aring out fromthe flange.

' integral annular reinforcing bead 63 at itsrim. With the" groove 61,the annular ,wall portion 55 is relatively, thin at. its juncture withflange 53. j

The'rearward plate or washer 43 has a flat circular central'portion65`which engages the inside face of the centralportion: 49 of thepackingmember 47 and an annuf lar peripheral. channel-sectionrim portion67 engageable inthe' annular V-shaped groove 590i the packing member...The4 central portion 65 of the rearward washer `43 has a central.opening 69 coaxial `with the opening 51 in portion 49:"of' thepackingmember 47. The forward plate.. or washer 45`is of conical .shapefitting in theconical recess 57'o`f the packing ymember 47, and has a-flat peripheral. flange y71'whichv engages the juncture of flange 53and theannular wall'por'tion 55 of the packing member. forward washertll'has a central opening 73 coaxial. with openings 51 and 69. Thewashers 43 and 45 and packing member.. 47 are held in assembly by abushing 75 extend#4 ing ,through openings 73, 51 and 69 and a nut 77threaded on the bushing. A stop plate 79 is secured to the largerend ofthe conicalforward washer 45" as by means `of ears 81: formedintegrally,v with plate '79 extending through notches 83 in plate79 andclinched overv on the outside of plate 791 Plate 79`has a slot 85 havingthe elongate centrally enlarged shape shown in Fig. 5.

At 87 is indicateda follower rod which extends throught'h'e'fllowerbushingjS andy nut 7,7.` The bushinghas Thev 3 counterbore89 containing packing 91 having a slidin sealing lit on the followerrod. The barrel 1 has a cap 93 threaded on its rearward end. Thefollower rod has a length somewhat greater than that of the barrel andextends slidably through a central opening 95 in the cap. The outer endof the rod 87 is formed as a handle as indicated at 97. The opening 95may be circular with a lateral notch as in the gun shown in U.S. Patent2,394,488, and the rod 87 may have a groove 99 as in said patent forlocking the rod in a retracted pulled-out position by angling the rod tobring the groove into the lateral notch. At the inner end of thefollower rod 87 is a cross-pin 101. The rod 87 may be turned to alignthis pin 101 with slot 85 in the stop plate 79 or to disalign it fromthis slot.

When the gun is to be used as a cartridge gun (i.e., loaded with acartridge of grease), the packing member 47 of the follower 21 ispositioned as shown in Figs. 1 and 2 with its annular wall portion 55extending in the direction toward the rearward end of the barrel 1 pastvthe rearward washer 43. The latter is of substantially smaller diameterthan the internal diameter of the barrel, such as to allow for theaccommodation of the annular wall portion 55 between the rim 67 ofwasher 43 and the internal surface of the cartridge. To load the gunwith a cartridge of grease, the pump P is removed from the barrel 1. Itwill be understood that the cartridge comprises a tube such as indicatedat T in Fig. 1 which is filled with grease and which, as supplied, hasclosure caps (not shown) at its ends. The tube T has a large opening atone end and a small opening at the other. The follower rod 87 is pulledout and locked in pulled-out position by angling it for engagement ofgroove 99 in the lateral notch of the opening 95 in the barrel cap 93.This pulls the follower 21 back to the rearward end of the barrel andholds it there against the bias of spring 23. The caps having beenremoved from the tube T, the tube T is iuserted into the barrel 1 withthe end of the tube T having the large opening being inserted first.

The pump P is then replaced on the barrel 1, and the follower rod 87unlocked from the barrel cap 93. Holding the follower rod 87 back sothat the pin 101 is located between stop plate 79 and the bushing 75,the follower rod is turned to disalign pin 101 and slot 85. Then thefollower rod is pushed in. This pushes in the follower 21. The packingmember 47 of the follower, being positioned as shown with the annularwall portion 55 extending in the direction toward the rearward end ofthe barrel,

has the form of a hollow nose and the annular wall portion is readilyradially compressed to cylindrical form as it enters the end of the tubeT so that it easily enters the tube and comes into sliding sealingengagement with the interior surface of the tube to force the grease inthe tube toward the pump P without leakage of grease past the packingmember. While the annular wall portion 55 is readily compressible forentering the tube T, the bead 63 stiffens the annular wall portion tothe extent sucient to prevent the pressure of the grease from breakingthe seal between the annular wall portion and the tube. Pressure isapplied by hand to the follower rod to expel any air that may have beentrapped by the ball check valve 37, and then the follower rod isdisengaged from the follower by aligning the pin 101 and slot 85 andpushing the rod in to the Fig. l position. Then the gun is ready foruse.

If the gun is to be loaded with bulk grease by means of a filler pumpthrough the ller nipple 41, the annular wall portion 55 of the packingmember 47 of the follower 21 is positioned as shown in solid lines inFig. 3 extending in the direction toward the forward end of the barrelpast the forward washer 45. The latter is of substantially smallerdiameter than the internal diameter of the barrel, such as to allow foraccommodation of annular wall portion 55 between the rim of washer 45and the internal surface of the barrel. The stated positioning isaccomplished, with the follower rod 87 and follower 21 removed from thebarrel, by bending the annular wall portion 55 around the ange 71 of theforward washer 45. The groove 61 permits the annular wall portionreadily to be bent. Grease is pumped into the barrel through the fillernipple 41 by means of the filler pump, the pressure of the greaseforcing back the follower 21. With the annular wall portion 55 extendingforward, the pressure of the grease acts to make it expand radiallyoutward and seal tightly against the internal surface of the barrel toprevent leakage past the follower.

If the gun is to be loaded by suction, the pump is removed, the forwardend of the barrel inserted into a container of grease, and the followerpulled back to suck grease into the barrel. For such loading, theannular wall portion 55 may be positioned either way, with somepreference that it is positioned as shown in solid lines in Fig. 3,particularly in a case where it may have taken a set in the Fig. 2position as a result of the gun having been used for a long time as acartridge gun.

In view of the above, it will be seen that the several objects of theinvention are achieved and other advantageous results attained.

As various changes could be made in the above constructions withoutdeparting from the scope of the invention, it is intended that allmatter contained in the above description or shown in the accompanyingdrawings shall be interpreted as illustrative and not in a limitingsense.

We claim:

1. In a lubricant gun comprising a cylindrical barrel for containingeither a cartridge of lubricant or bulk lubricant, one end of the barrelconstituting its rearward end and the other its forward end, kand a pumpat the forward end of the barrel, a follower for forcing lubricanttoward the pump, said. follower comprising a resilient cup-shapedpacking member having a base portion and an annular wall portion which,when unconfned, is of conical form aring outward from one face of saidbase portion, said annular wall portion extending rearward from saidbase portion when a cartridge is used in said barrel, and being adaptedto be flexed around the margin of said base portion to extend forwardfrom said base portion when the barrel is loaded with bulk lubricant,said annular wall portion of said packing member being thinner at itsjuncture with said base portion than rearward of said base portion forfacilitating the exing thereof.

2. In a lubricant gun as set forth in claim 1, said annular wall portionof said packing member having an integral annular reinforcing bead atits rim which is disposed on the inside of said wall portion when in itsrearwardly extending position and on the outside of said wall portionwhen in its forwardly extending position.

3. In a lubricant gun comprising a cylindrical barrel for containingeither a cartridge of lubricant or bulk lubricant, one end of the barrelconstituting its rearward end and the other its forward end, and a pumpat the forward end of the barrel, means comprising a follower forforcing lubricant toward the pump, said follower comprising a resilientcup-shaped packing member having a base portion and an annular wallportion which, when unconned, is of conical form flaring outward fromone face of said base portion, a rigid mounting forvsaid base portion ofsaid packing member, said mounting being substantially smaller than theinternal diameter of said barrel, said annular wall portion of saidpacking member extending rearward from said mounting when a cartridge isused in said barrel, said annular wall portion being adapted to beilexed to extend forward from said mounting when the barrel is loadedwith bulk lubricant, said annular wall portion of said packing memberbeing thinner at its juncture with said base portion than rearward ofsaid base portion for facilitating the flexing thereof, and saidmounting being formed to allow for the accommodation of saidannular wallportion either in its said rearwardly extending position or its said forWardly extending position.

4. In a lubricant gun as set forth in claim 3, said annular wall portionof said packing member having an integral annular reinforcing bead atits rim which is disposed on the inside of said wall portion when in itsrearwardly extending position and on the outside of said wall portionwhen in its forwardly extending position.

5. In a lubricant gun comprising a cylindrical barrel for containingeither a cartridge of lubricant or bulk lubricant, one end of the barrelconstituting the rearward end and the other its forward end, and a pumpat the forward end of the barrel, means comprising a follower forforcing lubricant toward the pump, said follower comprising a resilientcup-shaped packing member having a base portion and an annular wallportion which, when unconned, is of conical form flaring outward fromone face of said base portion, a rearward washer engaging said one faceof said base portion, a forward washer engaging the other face of saidbase portion, and means securing said washers together with said baseportion therebetween, said washers being of substantially smallerdiameter than the internal diameter of said barrel, said annular wallportion of said packing member extending rearward past said rearwardwasher when a cartridge is used in said barrel, said rearward washerbeing of such diameter as to allow for the accommodation of said annularwall portion between the rim of said rearward washer and the internalsurface of a cartridge, and said annular wall portion being adapted tobe flexed around the rim of the forward washer and to extend forwardpast said forward washer when the barrel is loaded with bulk lubricant.said annular wall portion of said packing member being thinner at itsjuncture with said base portion than rearward of said base portion forfacilitating the exing thereof, said forward washer being of suchdiameter as to allow for the accommodation of said annular wall portionbetween the rim of said forward washer and the internal surface of thebarrel.

6. In a lubricant gun as set forth in claim 5, said annular wall portionof said packing member having an integral annular reinforcing bead atits rim which is disposed on the inside of said wall portion when in itsrearwardly extending position and on the outside of said wall portionwhen in its forwardly extending position.

7. In a lubricant gun comprising a cylindrical barrel for containingeither a cartridge of lubricant or bulk lubricant, one end of the barrelconstituting its rearward end and the other its forward end, and a pumpat the forward end of the barrel, a follower for forcing lubricanttoward the pump, said follower being made of firm form-retainingresilient material and shaped like a cup, said follower having a portionof circular contour constituting the base of the cup and a singleannular wall portion only, said annular wall portion being of conicalform flaring outward from said base of the cup inone direction away fromthe base of the cup when said wall portion is unconfined, said wallportion extending away from the base of the cup in the direction towardthe rearward end of the barrel when a cartridge is used in the barrelwhereby it may be readily entered in a cartridge in the barrel throughthe rearward end of the cartridge with accompanying radially inwardcompression of the rim of said wall portion and resultant slidingsealing engagement of the rim of said wall portion with the internalsurface of the cartridge maintained by the stress in said wall portiondue to said compression, said follower being suciently thin in theregion of the juncture of said wall portion and said base for flexure ofsaid wall portion around the margin of said base to extend in thedirection toward the forward end of the barrel when the barrel is loadedwith bulk lubricant, the rim of said wall portion then being in slidingsealing engagement with the internal surface of the barrel and said wallportion then being adapted for radially outward expansion under pressureof lubricant in the barrel for sealing against the internal surface ofthe barrel.

Loweke Apr. 9, 1940 Rotter et al. Feb. 5, 1946

